Continuous mining machine



April 12, 1966 J. GONSKI CONTINUOUS MINING MACHINE 5 Sheets-Sheet l Filed Sept. 19, 1962 AApril 12, 1966 J. GoNsKl 3,245,723

CONTINUOUS MINING MACHINE Filed Sept. 19, 1962 3 Sheets-Sheet 2 INVENTOR Josep/1 Go/vsk/ ATToR/vf YS April l2, 1966 .1.csoNsKl CONTINUOUS MINING MACHINE 5 Sheets-Shea?l 5 Filed Sept. 19, 1962 .Il w H n O 4 2 7 7 4 7 l) m n /0 9/ 3 3 3/ 4 \\ll.%iid:t i v 3 E, I 8b /.J5 6 5&6@ 4 .MW ,w /w @il l O I l m 3 O n /w ILL M. 7 2 /v 2 4 O 2 INVENTOR. dase/z Gans/' ATTMEVS United States Patent 3,245,723 CQNTINUOUS MINING MACHINE Joseph Gonsai, Chicago, ill., assigner to Goodman Manufacturing Company, Chicago, lll., a corporation of Illinois Filed Sept. 19, 1962, Ser. N 224,674 Claims. (Cl. 299-59) This invention relates to, improvements in continuous mining machines.

In continuous mining machines of the class described, having .two side cutting m-ining heads angularly moved toward each other after having been sumped endwise into a working face of a mine, where the coal seam is thicker` than the diameter of the mining head, the seam must be mined, in benches, the rst mining operation usually being along the roof and the second mining operation usually being along the floor. This requires two sumping and lateral feeding operations together with one withdrawing opera-tion in order to completely mine a working face to the cutting depths of the side cutting angers.

While the use of two augers with one auge-r spaced in advance of lthe other has been contemplated, with such an arrangement of angers, benches or ledges are left along each rib, or a bench or a ledge may be le-ft along one rib and a relatively large bench or ledge, which may be termed a cusp is left at the center of the seam. These benches or ledges must be mined out before the machine can advance to a next mining and loading operation.

-A principal object of the present invention is to irnprove upon the foregoing types of continuous mining ma.- chines by utilizing two side ycutting angers to mine from the ribs to the center of a working face and by so driving and arranging the side cutting augers that the cutter bil-ts of one auger may -blend or interdigitate into paths of cutting of the cutter bits of the next vertically spaced auger, to enable the mining heads to be adjusted t-o mine in one operation, seams which are thicker than the diameter of a side cutting mining head.

A further object of the invention is to provide an improved form of continuous mining machine utilizing t-wo vertically spaced side cutting mining lheads in which the two mining heads are so driven and supported that they may be adjustably moved so the paths of cutting of the cutter bits of one auger project int-o the paths of cutting of ythe cutter bits of the next adjacent auger.

Still another object of the invention is to provide a continuous mining machine having two angularly movable boom arms supported adjacent the forward end of the machine for movement about vertical axes and having a side cutting auger carried by and supported in advance of each boom arm, in which the boom arms are vert-ically adjustable toward and from each other to blend the cutting paths of the augers into each other, to enable the angers to be vertically adjustable for completely cutting out seams of coal of less height than the combined diameters of the two auge-rs.

Still :another object of the invention is to reduce the size of the cusps projecting upwardly from the floor and downwardly -from the roof, left between the side cutting mining heads of a continuous mining machine by utilizing -two vertically spaced side cutting mining heads at each side of the machine movable inwardly toward Ithe center of .the machine during cutting, and by so supporting the mining heads, that they may cut in interdigitating relation with respect to each other and the cutters of the mining heads on each side of the ma chine may intcrdigitate as they move 4toward each other toward the center of the Working face.

Patented Apr. l2, 1965 ice These and other objects of the invention will appear from time to time as the following speciiication proceeds and with reference to the accompanying drawings wherein:

FIGURE l is a plan view of a continuous mining machine constructed in accordance with the principles of the present invention;

FIGURE 2 is a view in side elevation of the machine shown in FIGUR'E l;

FIGURE 3 is a diagrammatic view illustrating the cutting patterns oi the two sets. of side cutting mining heads when cutting in interdigitating relation with respect to each other and showing the angers in vertical section;

FIGURE 4 is a View in side elevation of two of the angers showing the angers cutting in interdigitating relation with respect to each other; v

' FIGURE 5 is a diagrammatic view showing the augers space-d to .cut seams thicker than the combined diameters of the two angers; and

FIGURE 6 is an enlarged fragmentary vertical sectional view. taken through one pair of -upper and lower boom arms and their support, with certain parts broken away.

In the embodiment of the invention illustrated in the drawings, I have shown in FlGURES 1 and 2, a mining machine lil of the side cutting continuous mining type, adapted to cut out and load an entire seam of coal by advancing two vertically spaced side cutting mining heads 11, 11 on each side of the machine endwise into the working face of a coal seam when in the laterally extended positions shown by dashed lines in FIGURE l, by advance of the entire machine toward the working face, and by feeding the mining heads toward each V other across .the working face.

The mining machine 10 includes generally a main frame 12. mounted on a pair of laterally spaced continuous traction tread devices 13, 13, for propelling the machine from working -place to working place and for advancing the machine toward a working face to feed the two side cutting mining heads 11, 11 on each side of the machine into .the working yface in a generally endwise direction. The continuous traction tread devices 13, 13 may be independently driven in a conventional manner at either high tramming or low feeding speeds and are no part of the present invention, so need not herein be shown or described further.

j Extending along the machine from a position in advance of the forward en-d of the main frame l2, adjacent the ground, is a c-onveyor 15 having a laterally flexible discharge end portion 16 adjustable to discharge into shuttle cars, room conveyors and the like, to accommodate the material mined to be carried away from the machine as it is mined. inclined aprons 18, 18 may extend along opposite sides of an inclined elevating portion 19 of the conveyor to guide the mined material onto the conveyor as it is progressed rearwardly to the conveyor by the side cutting mining heads 11, 11. The conveyor may lbe a center strand endless chain and ight type conveyor of the laterally flexible type and is no part of the present invention so need not herein be shown or described further.

i An individual angularly movable feeder frame 21 forms a support for each pair of vertically spaced side cutting mining heads `11. As shown in FIGURE l, each yfeeder frame 21 has a base plate 22 extending inwardly beneath conveyor 15 and pivotally mounted on the main frame 12 on la vertical pivot pin 23.

Each feeder frame 21 also includes a pair of spaced outer and inner upright trunnion supports 24 and 25, respectively, having ltrunnion pins 26 extending inwardly 3 therefrom forming mountings for parallel spaced arms 27, 27 of Ian upper boom arm 29 and for Iparallel spaced arms 30, 30 of a lower iboom `arm-31. The arms 27, 27 of the upper boom arm 29 extend along opposite sides of a tilting frame 28 forming a support for the upper mining head 11, and are pivotally connected to said tilting frame as by la transverse pivot pin 32 connected between said boom arms.

The arms 30, 30 of .the lower boom arm 31 extend 1 connected at its lower end to an arm 42of the tilting` frame 33 on a pivot pin 43.

The lowertilting frame 33 is held in position and is langularly moved about the axis -of the pivot pins 35, as .by a hydraulic cylinder 45 having a piston rod 46 eX- tensible therefrom. The piston rod 46 is .pivotally connected to the tilting frame 33 by a pivot pin 47,`while the cylinder 45 is pivotally connected to the arms 30, Iby a pivot pin 49.

The cylinder and piston rod 46 may thu-s adjust fthe angular positi-on of the lower tilting frame 33` and the side cutting mining head 11 suppo-rted thereon with respect to the ground, while the hydraulic cylinder 41 and piston rod 39 may adjust the angular relation of the upper tilting frame 2S and side cutting mining head y11 supported thereby with respect -to the lower tilting frame to .support the upper mining head 11 in parallel relation with respect to the lower mining head 1:1.

The boom a-rms 27, 27 are held in fixed relation with respect to the boom. arms 30, 30and Iare adjustably moved toward and from each other by a hydraulic jack including a cylinder 50 pivotally connected between the boom arm-s 27, 27 on a pivot pin 51, and a piston rod 52 extensibly .and retractibly movable with respect to the cylinder 50 and pivotally connected between the boom 'arms 30, 30 on a pivot pin 53. The hydraulic cylinder 50 and piston rod 52 thus hold the boom arms 27,27

and 30, 30 in fixed relation with respect to each other and` serve to adjust the two mining heads 11, 11 to cut a seam of the required thickness, 4and to hold said mining heads in adjusted relation with respect to each other.

The boom arms 27, 27 and 30, 30 are adjustably moved as a unit about the axes of the trunnion pins 26 by a hydraulic jack including 1a cylinder 55 pivoted to a sup port bracket 56 extending upwardly of the base plate 22 of the associated feeder frame 21, on a transverse pivot pin 57. A piston rod 59 is extensibly and retractably movable with respect to the cylinder 55 and is pivotally connected to the lower boom arms 30, 30 on atransver-se pivot pin 60.

A drive motor 61 for the two vertically spaced mining heads 11, 11 is suitably mounted between the lower boom yarms 30, 30 and extends upwardly into the space between the two upper boom arms 27, 27. The motor 61 may be a well known form of electrical motor commonly used to drive mining machine cutter mechanisms, and as generally shown in FIGURE 2, has a speed reducer housing 63 extending forwardly :from the forward end thereof con-` taining reduction gearing driving two ventically spaced lower land upper output shafts 64 and 65 respectively. The output shafts 64 and 65 form drive members for universal couplings 66 and 67 respectively, driving extensible drive shafts 68 and 69 respectively, havingexible couplings 70 and '71 connectedto the respective forward ends thereof for driving :the individual mining heads 11, 11. The drive connections to the two mining heads 4: I may be conventional for-ms of universal extensible drive connections and are no part of the present inventon'so are only shown diagrammatically herein.

The mining heads =11, 11 are mounted on the respective tilting frames 28 and 33 for rotation about axes extending longitudinally of the boom arms 27, 27, land 30, 30 in a suitable manner, and as shown in FIGURES 3, 4 and 5 comprise longitudinally extending shafts 73`having helical conveyor scrolls extending therealong for Isubstantially the length of said shafts. The conveyor scroll 75 has a series of cutter bits 76 extending forwardly of the forward e-nd thereof and also has cutter bits 77 extending radially of said scrolls and pitched to cut as said scrolls are fed sidewise along a working face after first having been sumped therein -by endwise movement of said scrolls into the working face.

A cuttings conlining member 79 islmounted on each enter lower boom anni Stlin outwardly spaced relation with respect thereto and extends forwardly therefrom from a position clearing the ground, .upwardly Vbeyond the upper mining head 11,fwhen the lower mining head i-s positioned t-o lcu-t along the ground,'to confine the cutting-s to the scrolls 75, 75 to be conveyed thereby towards the conveyor, to be loaded onto said conveyor as the mining heads' are fed yinwardly toward each other.

As .shown in FIGURES `3, 4 and 5, the scrolls 75 of the two vertically spaced mining heads 11, 11 are pitched A in opposite directions, that is the upper scroll at the right hand side ofy the machine when looking towards the forward end of the machineis a left handscroll and is driven in .a clockwise direction. The lower scroll on the same side of the machine is a right hand scroll and is rotatably driven in a counterclockwise direction. The upper lscroll on the left hand side of the machine is a right hand scroll and is driven in a counterclockwise direction, while the lower scroll is .a left vhand scroll and is driven in a clockwise direction. The cutter bits 77, 77 of all four scrolls are driven vto approach each other towards the vertical and horizontal center of .the seam and .the four scrolls are driven to progress the cuttings towards the conveyor 15.

As shown in FIGURE 4, the helical or spiral arrangements of the four scrolls 75 are such that when the upper and lower mining heads 11', 11 are adjustably moved toward each other, the peaks of one scroll will move into the valleys of the next adjacent scroll, with the result that the cutting paths of the cutter bits 77 of the two vertically spaced scrolls may blend or move into interdigitating relation with respect to each other, and the workingl face may be mined when the mining heads are so adjusted, by sidewise movement of the mining heads along the working place toward the center of the working place.

The speeds of rotation of the four mining heads 11, 11 are the same and since vthe scrolls on opposite sides of the machine are of opposite hands and are driven in opposite directions, the four mining heads may move, inwardly toward each other into positions where the cutting paths of the cutter bits and scrolls on the right hand mining heads interdigitate with the cutting paths of the vcutter bits and scrolls on the left hand mining heads at the center of the working face, as diagrammatically illustrated in dashed lines in FIGURES l and 3.

The mining heads on ,each side of the machine may be maintained at the same rates of speed by electrically connecting the motors 61, 61 to operate in synchronism with each other. That is, the elds (not shown) of the two motors may be connected in series and the armatures (not shown) may be connected in parallel. The foregoing connections of the two motors are well known to those skilled in the art and are no part of the present invention so need not herein be shown or described further.

The feeder frames 21, 21 and mining heads 11, 11 supported thereby are angularly moved to feed the mining heads 11,11 inwardly toward each other and are held in laterally extended positions to accommodate the mining means of individual hydraulic jacks 80, 80 including cylinders 81 pivotally connected to the main frame 12 on vertical pivot pins 82. Piston rods 83 extensibly and re* tractably movable with respect to the cylinders 31 extend between the `furcations of a bifurcated portion 85 of each bracket 56 and are pivotally connected thereto on vertical pivot pins 86.

In the operation of mining, where mining a relatively thick seam of coal, the two mining heads 11 on each side of the machine may be adjusted in vertically spaced relation with respect to each other with the upper mining heads positioned to cut downwardly from the roof of the mine towards each other and the lower mining heads positioned to cut upwardly from the floor of the mine towards each other. With the mining heads so adjusted, a cusp is left between the upper and lower mining heads (FIGURE i5) but this cusp readily breaks off and is progre'ssed toward the conveyor to be loaded thereonto during the mining operation.

In mining a thin seam of coal the two mining heads on eachy side of the machine may be adjusted as shown in FIGURE 3, to cut in blending or interdigitating cutting paths and at the start of the mining operation may be positioned in the laterally extended positions shown by dashed lines in FIGURE l, along each rib of the working place. The mining heads may then be held in this position by the hydraulic jacks 80. The four mining heads properly adjustedto effect cutting of the upper mining heads towards each other downwardly from the roof of the seam and of the lower mining heads to cut towards each other upwardly from the floor of the seam may then be rotatably driven by the two motors 61 at the same rates of speed. The mining heads being held in the laterally extended positions shown in FIGURE l, may be fed generally endwise into the working face to the required depth byvoperation of the traction tread devices 13. When the mining heads have been sumped into the working face to the required depth, the machine being stationary with respect to the ground, the four mining heads 11, 11 may then be advanced inwardly toward each other at suitable feeding speeds by operation of the hydraulic jacks 80, feeding the mining heads across the working place inwardly toward each other, with the forward end portions of the scrolls 75 and the cutter bits 77 projecting therefrom, cutting into interdigitating relation with respect to each other at the center of the working place until inward feeding movement of said mining heads is stopped by suitable stop means (not shown) which may either be in the hydraulic system controlling the ow of hydraulic fluid to the jacks 80, or which may be mechanical stop means of a conventional form. f

As the inward limit of movement of the mining heads is reached, the machine is moved backwardly a slight amount, su'icient to clear the mining heads from the working face, and the mining heads are then moved laterally to the laterally extended positions shown in FIGURE 1 and again sumped into the working place and moved thereacross to the inwardly extending dashed line positions shown in FIGURES l and 3.

It may be seen from the foregoing that by supporting the two mining heads on each side of the machine one above the other and by so arranging the scrolls that the mining heads may cut in blending or interdigitating cutting patterns, coal seams of various heights may be completely mined in a single mining operation, and that the necessity of mining in benches or of cleaning up the Working place by mining the benches or ledges left either at the ribs or at one rib and the center of the working place has been eliminated.

It may further be seen that since all of the mining heads rotate at synchronized speeds, they may also cut in interdigitating cutting paths as they approach each other, to thereby reduce the size of the cusps between the mining .heads and extending upwardly from the mine floor and 6 depending from the mine roof to such proportions that they need not be mined out by separate mining operations.

While I have herein shown and described one form in which my invention may be embodied, it may readily be understood that various variations and modifications in the invention may be attained without departing from the spirit and scope of the novel concepts thereof as defined by the claims appended hereto.

I claim as my invention:

1. In a continuous mining machine,

a mobile main frame,

two vertically spaced aligned side cutting mining heads projecting forwardly of said main frame,

each mining head including a horizontal shaft having a scroll extending therealong and having cutter bits projecting therefrom,

the upper of said scrolls being of one hand and the lower of said scrolls being of an opposite hand,

a motor,

means driven by said motor for rotatably driving said scrolls in opposite directions at the same rates of speed to progress the mined material rearwardly toward said main frame,

a feeder frame mounted on said main frame for pivotal movement with respect thereto about a Vertical axis, T

individual boom arms for said mining heads transversely pivoted to said feeder frame and extending in advance thereof,

means supporting said mining heads on said boom arms to extend forwardly therefrom,

means for maintaining said boom arms and mining heads in fixed relation with respect to each other and for vertically adjusting said boom arms and mining heads with respect to each other, to adjustably move said scrolls toward and from each other and to position said scrolls to cut in interdigitating relation with respect to each other.

2. In a continuous mining machine,

a mobile main frame,

a feeder frame pivotally mounted on said main Vframe for movement with respect thereto about a vertical axis,

a pair of boom arms transversely pivotally mounted on said feeder frame and extending in advance thereof,

a side cutting mining head carried by said boom arm and extending in advance thereof,

each side cutting mining head including a longitudinal shaft having a scroll extending therealong having cutter bits projecting radially therefrom, said scrolls being in vertical alignment with respect to each other and one scroll being of an opposite hand from the other scroll,

means for driving said scrolls in opposite directions at the same rates of speed,

means interconnected between said boom arms for adjustably moving said boom arms and mining heads independently of each other to bring said scrolls from vertically separated positions into interdigitating relation with respect to each other,

and other means connected between said feeder frame and one of said boom arms for adjustably moving said boom arms vertically as a unit about their axis of transverse pivotal mounting on said main frame.

3. A continuous mining machine in accordance with claim Z,

wherein a feeder frame,

boom arms and side cutting mining heads are mounted on each side of said main frame and project forwardly therefrom to effect cutting by movement toward each other and wherein the scrolls of opposite upper mining heads and of opposite lower mining heads are of opposite hands and are driven in opposite directions to cut towards the center of the working place and to cut in blending cutting paths antenas as they approachthe transverse center of theV working place.

4. In a continuous'mining machine,

' a mobile main frame, v

a feeder frame mounted on said main frame for lateral swinging movement with respect thereto about a vertical axis,

power means for laterally moving said feeder frame about said vertical axis,

a pair of vertically spaced boom arms pivoted to said feeder frame for movement about a common transverse axis,

power means retaining said boom arms in fixed spaced relation with respectA to each other and vertically adjusting saidboom arms with respect to each other,

other power means connected between said kfeeder frame and one ofV said boom arms for vertically moving said boom arms together about said transverse axis,

` a side cutting mining head rotatably supported on each boom arm and extending in advance thereof,

said mining heads being vertically aligned and having cutter bits projecting radially therefrom and spaced radially from the axes of rotation thereof,

means for rotatably driving said mining heads in opposite direction at the same rates of speed,

said power means retaining said boom arms in fixed spaced relation with respect to each other and ver- 'tically adjusting said boom arms with respect to each other to position said cutter bits to cut in intersecting cutting paths and to vertically move said 'boom arms and mining heads apart to mine a seam thicker than the combined diameters of the cutting paths of said cutter bits.

5. A continuous mining machine in accordance with claim 4, wherein a feeder frame is pivotally mounted at each side of said main frame,

wherein each feeder frame has a pair of vertically spaced boom arms projecting therefrom and having side cutting mining heads mounted thereon,

wherein the opposite upper mining heads and the opposite lower mining heads are driven in opposite directions to cut towards each other and towards the center of the working place in blending cutting paths asl they approach the center of the working place.

6. 1n a continuous mining machine, a mobile main frame,

a feeder frame mounted on said main frame for lateral swinging movement with respect theretov about a vertical axis,

CII

vertically aligned upper and lower side cutting mining heads spaced in advance of said feeder frame,

vertically aligned upper and lower boom arms transvversely pivoted to said feeder frame,

each boom arm forming a support for a respective side cutting mining head,

supporting the associated side cutting mining head to project forwardly therefrom,

means for laterally moving said feeder frame about said vertical axis,

means for holding said boom arms in fixed spaced relation with respect to each other and for vertically adjusting said boom arms toward and from each other,

other means connected between said feeder frame and one of said boom arms for vertically moving said boom arms as a unit,

a motor,

means driven by said motor' for rotatably driving said mining heads in opposite directions,

each mining head including a longitudinally extending shaft rotatably dritten bysaid motor and having a scroll extending thercsalong having cutter bits projectina Qutwardly therefr om,

thes'crolls of said vertically aligned upper and lowerV mining heads being of opposite hands and driven in opposite directions at thesamefrates` of speed and being so positioned on said` shafts as to accommodate adjustment of said mining heads toward each other to rotate together in interdigitating relation with respect' to each other. 7. In a continuous mining machine, a mobile main frame, a feeder frame mounted on said main frame for lateral swinging movement with respect thereto about a vertical axis,

two vertically aligned side cutting mining heads spaced in advance of said feeder frame,

two vertically aligned boom arms transversely pivoted to said feeder frame, each boom arm supporting an associated side cutting mining vhead to project in` means driven vby said motor for rotatably driving saidy mining heads in opposite directions at the same rates' of speed,

each mining head including a longitudinally extending shaft rotatably drivenby said motor andhaving a scroll extending therealong having cutter bits project ing outwardly therefrom,

means for transversely pivoting said scrolls with respect to said boom arms and for retaining said scrolls in fixed relation with respect to said boom arms,

and. said means connected between said boom` arms for vertically adjusting said boom arms with respect to each other having sufcient travel 'to bring said scrolls into interdigitating relation with respect to each other.

8. In a `continuous mining machina,

a mobile main frame,

a feeder frame mounted on said main frame for lateral swinging movement with respect thereto about a vertical axis,

hydraulic jack means for moving said feeder frame about said vertical axis, two spaced vertically aligned side cutting mining'heads extending in advance of said feeder frame,

support means for said mining heads including upper and lower boom arms pivotally mounted on said feeder ,frame for movement with respect thereto about a common transverse axis,

hydraulic jack means for holding said boom arms in fixed relation with respect to each other and vertically adjusting said boom arms with respect to each other to adjust the cutting positions of said side Vcutting mining heads,

other hydraulic jack means for vertically moving said boom arms together about said common transverse axis,

said mining heads each comprising a drive shaft rotat-y ably supported by and extending in advance of the associated boom arm and a scroll extending-along said drive shaft having cutter bits projecting therefrom,

a motor,

means driven vby said motor for driving said drive shafts and scrolls at the same rates of speed in opposite directions and driving said cutterbits on each scroll to cut toward each other in the direction of lateral movement of said mining heads, and said scrolls beingk of opposite hands to effect progression of the mined materialtoward `said main frame and 9 to enable said scrolls to be adjustably moved into interdigitating relation with respect to each other, to position said cutter bits to cut in blending cutting patterns.

9. In a continuous mining machine,

a mobile main frame,

a feeder frame mounted on said main frame for lateral swinging movement with respect thereto about a vertical axis,

hydraulic jack means for moving said feeder frame in feeding and return directions,

two spaced vertically aligned side cutting mining heads extending in advance of said feeder frame,

support means for said mining heads including upper and lower boom arms pivotally mounted on said feeder frame for movement with respect thereto about a common transverse axis,

an individual tilting frame transversely pivoted to the forward end of each boom arm and forming a bearing support for an associated mining head,

hydraulic jack means connected between the lower of said boom arms and the associated tilting frame for tilting said tilting frame and the side cutting mining head mounted thereon,

other hydraulic jack means connected between said tilting frames for tilting the upper of said tilting frames,

hydraulic jack means connected between said boom arms for holding said boom arms in fixed spaced relation with respect to each other and moving said boom arms toward and from each other and thereby adjusting the vertical positions of said mining heads,

other hydraulic jack means connected between said feeder frame and one of said boom arms for pivoting said boom arms together about their axis of transverse connection to said feeder frame,

a motor for driving said mining heads in opposite directions at the same rates of speed,

each mining head including a drive shaft rotatably supported in the associated tilting frame and extending 4 forwardly therefrom, and a scroll extending along said shaft,

said scrolls being of the same pitch and diameter and of opposite hand to accommodate the movement of one scroll into interdigitating relation with respect to the other,

to effect the continuous mining of a seam of less thickness than the combined diameters of the two mining heads.

10. A continuous mining machine in accordance with claim 9,

wherein a feeder frame is provided at each side of said main frame and wherein each feeder frame carries a pair of upper and lower boom arms, each rotatably supporting a mining head, wherein the mining heads are vertically and horizontally aligned and opposite upper mining heads and opposite lower mining heads are driven in opposite directions to cut towards each other and towards the center of the working place and are movable into interdigitating relation with respect to each other and mining by angular movement of said feeder frames toward the center of the machine to positions wherein the side cutting mining heads on opposite sides of the machine move into positions to cut in intersecting cutting paths as they approach the center of the Working place.

References Cited by the Examiner UNITED STATES PATENTS 1,303,797 S/1919 Holmes 299-71 2,801,091 7/1957 Joy 299-71 X 2,920,879 1/ 1960 Driehaus 299-73 X 2,967,701 1/ 1961 Wilcox 299-73 X 2,979,319 4/ 1961 Anderson 299-71 3,066,924 12/ 1962 Queer 299-68 FOREIGN PATENTS 560,813 7/ 1923 France. 322,894 7/ 1920 Germany.

CHARLES E. OCONNELL, Primary Examiner.

BENJAMIN HERSH, Examiner. 

1. IN A CONTINUOUS MINING MACHINE, A MOBILE MAIN FRAME, TWO VERTICALLY SPACED ALIGNED SIDE CUTTING MINING HEADS PROJECTING FORWARDLY OF SAID MAIN FRAME, EACH MINING HEAD INCLUDING A HORIZONTAL SHAFT HAVING A SCROLL EXTENDING THEREALONG AND HAVING CUTTER BITS PROJECTING THEREFROM, THE UPPER OF SAID SCROLLS BEING OF ONE HAND AND THE LOWER OF SAID SCROLLS BEING OF AN OPPOSITE HAND, A MOTOR, MEANS DRIVEN BY SAID MOTOR FOR ROTATABLY DRIVING SAID SCROLLS IN OPPOSITE DIRECTIONS AT THE SAME RATES OF SPEED TO PROGRESS THE MINED MATERIAL REARWARDLY TOWARD SAID MAIN FRAME, A FEEDER FRAME MOUNTED ON SAID MAIN FRAME FOR PIVOTAL MOVEMENT WITH RESPECT THERETO ABOUT A VERTICAL AXIS, INDIVIDUAL BOOM ARMS FOR SAID MINING HEADS TRANSVERSELY PIVOTED TO SAID FEEDER FRAME AND EXTENDING IN ADVANCE THEREOF, MEANS SUPPORTING SAID MINING HEADS ON SAID BOOM ARMS TO EXTEND FORWARDLY THEREFROM, MEANS FOR MAINTAINING SAID BOOM ARMS AND MINING HEADS IN FIXED RELATION WITH RESPECT TO EACH OTHER AND FOR VERTICALLY ADJUSTING SAID BOOM ARMS AND MINING HEADS WITH RESPECT TO EACH OTHER, TO ADJUSTABLY MOVE SAID SCROLLS TOWARD AND FROM EACH OTHER AND TO POSITION SAID SCROLLS TO CUT IN INTERDIGITATING RELATION WITH RESPECT TO EACH OTHER. 